When Los Angeles Lakers guard Sasha Vujacic proposed to Maria Sharapova earlier this month, he did so with a ring befitting a three-time Grand Slam champion.

Since accepting Vujacic's proposal, Sharapova has been seen in public wearing a huge diamond ring that is believed to have cost as much as $250,000. According to a jewelry expert contacted by US Weekly, Sharapova's engagement ring is an 8-carat, cushion-cut diamond resting on a split-shank platinum band.

[Photos: Celebrities dazzle in diamonds]

A quarter-million dollars is a whole lot of money to spend on a ring, but considering how much money Vujacic makes a year, he may have gotten off easy. As my mom constantly reminds me, a man is supposed to spend two months salary on a ring. Since Vujacic is scheduled to make $5.5 million this year with the Lakers, that would equate to buying a ring worth $912,000. Of course, that two-month rule probably doesn't apply to celebrities, or else Bill Gates would have had to have given his wife a diamond the size of the Rock of Gibraltar.

While Vujacic is a multi-millionaire thanks to his basketball talents, he won't be the primary breadwinner of the family. Last year, Forbes estimated Sharapova earned $25 million in winnings and endorsements. Can't imagine there are too many other NBA players who will bring home paychecks one-fifth of that of their wives.